Picture-projecting apparatus.



W. V. F0 "Y.

PICTURE PROJECTING APPARATUS.

APPLICATION FILED SEPT. 18, I91].

Patented July 30, 1918.

2 SHEETSSHEET I.

qgwwww WILL/0M VINCE/Y7" F015) 3511 6 307,142!

W. V. FOLEY. PICTURE PRQJECTING APPARATUS.

APPLICATION FILED SEPT. I8. 1911.

1 ,273,843. Patented July 30, 1918.

. I 2 s H E E TSSHEFT Z.

UNITED STATES PATENT OFFICE.

WILLIAM VINCENT FOLEY, OF NEW BRUNSWICK, NEW JERSEY.

PICTURE-F301] ECTING APPARATUS.

Specification of Letters Patent.

Patented July so, 1918.

Application filed September 18, 1917. Serial No. 191,926.

To all whom it may concern:

Be it known that I, WILLIAM VINoEN'r FOLEY, a citizen of the United States, residing at New Brunswick, in the county, of Middlesex and State of New Jersey, have invented certain new and useful Improve' chine and of my new reflector. This view is taken at a line corresponding to line 22 of Fig. 2. I

Fig. 2 is a top plan elevation of the machine shown in Fig. 1.

Fig. 3 is a front, and

Fig. at a rear elevation of my new reflector, removed; and

Fig. 5 is an edge view thereof.

The object of the invention is to produce a reflector particularly adapted for use in connection with incandescent electric lamp bulbs and of a construction and mode of operation that conserve to a greater extent than heretofore in illumination, the light rays proceeding from the source of light. Various kinds or types of sources of light may be used and I do not intend herein to limit my invention, so far as the reflector itself is concerned, to use in connection with electric incandescent lamps, for my reflector may be used with any appropriate source of light with new beneficial results; and I note that when it is used as a reflector in any way in which its concave reflecting surface is visible, such surfaceis of itself ornamental both when illuminated and when not illuminated.

Considered with reference to use of the reflector in picture-projecting machines and especially with reference to motion p cture machines, objects and advantages of my in,-

vention considered as a whole are: My new .machine can be used to advantage because its function is to produce two or more re.- flected images of the source of light and in concentrating or focusing the light rays from said images on one or more given points; it can be used with an electric lamp bulb of appropriate candle power instead of with arc-lights now in frequent use in motion p1cture pro e'ctmg machines, and with various attendmg economical advantages;

and it is constructed with a forced air ventilation whereby the life of the incandescent lamp bulb and ofthe reflecting surfaces if they are of silvered glass are advantageously prolonged Referring to the drawings, the concave surface of the concavo-convex casing 1 is lined at its bottom with a preferably parabol1c mirror 2, and from the annular line or edge of ,the mirror 2'to the brim or edge of the casing, with two series of flat-faced reflecting surfaces whichin the inward serles are indicated by 3 and in the outward series by 4. All these mirror surfaces 3 and 4 of which there are a multiplicity in each series, are made 'of one concave-convex mirror of any suitable material but ordinarily of glass silvered on its back, in order to prevent refraction which would occur if they were made in separate edgewise-abutted pieces; the concavo-convex structure having a smaller rear opening at 5 to fit the brim of the rearmost concave mirror 2 and a larger front opening adjacent the front brim of the disk-shaped casing.

The flat mirror surfaces 3 are polygonally disposed in the transverse direction, that is in the circumferential cross-sectional direction of the casing, each being disposed at an angle to the other;' and each is disposed 'slantingly upwardy and outwardly at an angle to a central axis through the casing. The flat mirror surfaces 4 have a corresponding polygonal relation one to the other and are severally slanted upwardly and outward.

I employ a considerable number of these mirror surfaces 3 and 4 in each series, the number of such surfaces being variable and the number of series of such flat mirror surfaces being also variable.

The numberv of the flat mirror surfaces 3 and 4 in each series depends largely on the of the box.

and dimensions, the areas and shapes of the mirror surfaces 3 and 4 maybe varied accordingly; and while I have used in practice and have also shown herein two series of the flat mirror surfaces 3 and; it may well be that curvature of such surfaces would be equally or approximately as eflicient as the flat mirror surfaces, and I do not intend to limit my invention to details by changes in which my invention, in relation to the form of the reflecting surfaces, can be avoided. The fact is, according to my present information, that I am the first to produce a concave reflecting surface which is characterized by a multiplicity of polygonally disposed reflecting surfaces to inclose a source of light and reflect a multiplicity of images of the source of light. The result of such arrangements is to concentrate or focus the rays of light from such multiplicit of images on the object or objects to be ill uminated with an attendant brilliancy of illumination strikingly in excess of thatobtained from the use of any other reflector known to me.

The reflector is for picture projection mounted in a box? as at 8. The electric light bulb 9 is mounted within the concavity of the reflector, an edge of the latter and of the casing being recessed at 10 to permit the location of the bulb and its contained filament in the concavity. The bulb-socket 11 is supported in an opening in the boxtop. The electric lamp, for use in projecting pictures, is preferably of a size to fill and project from the concavity of the mirror with an air space left between the bulb and the opposed wall of the reflector.

The box is provided at its lower portion with an air-intake port 12 from which the air-supply tube 13 extends, the tube being provided with a fan 14 for blowing air into the box-chamber where it flows upwardly into and around the reflector and light bulb, cooling the surfaces thereof and carrying off the heat through the vent 15 in the top wall This cooling is of economic importance for reasons stated. The fan is driven in any suitable way and its operation produces a positive current through the box chamber while the machine is in use. Forwardly of the reflector and source of light, the box is equipped with suitable lenses 16, shown in a well-known form of condenser lens.

The parabolic or concave bottom-forming mirror 2 and the flaring arrangement of the polygonally arranged reflecting surfaces 3 constitute the most effective form of my new mirror that I have yet devised in connection with the electric light bulb which must be inserted into the chamber of the mirror structure in front of the'b'ottom-forming mirror 2, and to obtain the best effect from a side of the mirror-forming structure so as to leave the mirror 2'intact; and in order that all the mirrors may coact to reflect the light rays properly into and through the condenser lens structure. For the purposes of this invention the cooperating concave bottomreflector and the reflecting surfaces 3 and 4 must coiiperate with the light for reflection of the light rays to the condenser lens in such wise that the light rays must pass parallel one to the other through the condenser lenses at right-angles to the flat surfaces of the lenses, which flat surfaces are directly opposed to the bottom concave lens. After passing in parallelism through the condenser lens, the light rays become 1focused at a point beyond the condenser ens.

I am aware of Grays Patent No. 1,133,955 of March 30, 1915, in which an apparatus for photographic enlargement is set forth and in which the reflector and incandescent electric lamp are so arranged that the axis of the lamp is in alinement with the point on which the reflected rays converge in the lens tube. In this Gray patent it is stated that maximum efliciency on the part of a reflector of his type, and when used in connection with the photographic enlarging apparatus, can be had only when the maximum number of reflected raysare directed into the lens barrel and they are shown converging in the lens tube or barrel, and obviously converge at the center of whatever'kind of lens is assumed to be in the tube. There is no suggestion in the Gray patent that the lens is a condensing lens, and Grays drawing and description plainly indicate that there is no intention to pass rays in parallelism through the lens so that they can converge at a focalpoint beyond the lens and exteriorly of the structure. I therefore disclaim all that is shown in the Gray patent.

What I 'claim is:

1. In a picture-projecting machine, the combination of an incandescent electric light bulb, with a condenser lens and a mirror, the bulb being intermediate the lens and mirror, and the mirror comprising a bottom-= forming concave mirror and an outwardly flaring mirror having a plurality of sets of plane mirrors which in each set are angularly disposed one to another.

2. A structure as specified in claim 1, wherein said series of angularly disposed mirrors are integral.

3. In the structure of claim 1, the combination of an interiorly and outwardly flaring mirror having a lamp-receiving opening in its slde wall forwardly of its' bottom portion; and as a. central lining of its bottom portion, a. concave bottom-forming mirror; and as a. lining for its interior side wall forwardly of such bottom-forming mirror, a plurality of series of mirrors, the mirrors of each series being at an'angle one to the other; and in such side-wall mirror 10 lining, an 0 ening for reception of an electric light bu b, such opening being coincident with the opening in the side wall of the casing.

In testimony whereof I have hereunto set 15 myhand this 15th day of September, 1917.

WILLIAM VINCENT FOLEY. 

